Alrosa has concluded the sale of its 41 per cent share in Catoca, Angola’s state-controlled diamond miner, drawing an end to a 32-year partnership.
It has been acquired by Taadeen, a subsidiary of Oman’s sovereign wealth fund.
The move was announced last November, after Angola’s mineral resources minister Diamantino Azevedo described Alrosa, the sanctioned Russian miner, as a “toxic partner”.
The transfer was formalized on 26 May and leaves Angola’s national diamond company Endiama EP retaining a controlling 59 per cent.
Catoca’s updated website now lists its company shareholder structure as: “Endiama EP (National Diamond Company of Angola) – 59% Taadeen (Subsidiary company of the Sovereign Wealth Fund of Oman) – 41%”.
No financial details of the share transfer have been released.
Alrosa acquired 32.8 per cent of Catoca shares in 1992, soon after the country’s long-running civil war came to an end, and increased its stake to 41 per cent in 2018.
Karelian Diamond Resources has registered its Lahtojoki mining concession in the Finnish land registry, advancing its plan to develop what could become the European Union’s first diamond mine.
This registration, handled by the Finnish mining authority TUKES, allows the company to proceed with further development plans for the Lahtojoki diamond deposit.
TUKES had previously approved the concession and is also responsible for issuing the mining certificate.
Karelian noted that a hearing on compensation matters related to the project has been postponed until the Fall of 2025, potentially impacting the timeline for full-scale operations.
Lahtojoki is known for its high-quality gem diamonds, including rare pink and coloured stones that can fetch up to 20 times more than typical colourless gems. The company believes the diamondiferous kimberlite pipe has the potential to support a profitable, low strip ratio open-pit operation.
The Dublin-based company is simultaneously exploring and advancing other assets in Finland, containing nickel, copper and platinum group elements. It is also advancing exploration at a site in the Kuhmo region where it aims to discover the source of a rare green diamond it found in 2022.
Africa-focused Petra Diamonds has scrapped regular diamond tenders in favour of opportunistic sales as the market for rough stones continues to slump.
The miner reported $53 million in sales from its fifth and sixth tenders of the year, covering production from its two South African mines. Petra will now report sales on a quarterly basis instead of following a fixed tender schedule.
“In response to fluctuations in diamond prices and demand, the company no longer follows regular tender cycles and may postpone portions of tenders or sell goods as run-of-mine,” the company said.
The strategic pivot mirrors De Beers’ reported off-market sales of discounted diamonds to selected clients. The move aimed to reduce inventory without officially slashing prices.
Petra said it sold 613,747 carats in the two tenders, a 29% increase from its fourth tender in February. The average price was $86 per carat, about 4% higher than February’s auction. On a like-for-like basis, prices were down 16% compared to the first six tenders of 2024, largely due to lower-value goods.
Year-to-date, the company has sold 2.39 million carats for $239 million, down from $329 million over the six first tenders of its 2024 financial year.
Petra delayed its April and May tenders due to a weaker product mix at its flagship Cullinan mine. The Finsch mine, meanwhile, saw improved pricing thanks to better ore access. The company expects an improved product mix as it ramps up production from the CC1E and the western side of the C-Cut block.
Petra also drew an additional $33 million in debt, bringing its consolidated net debt to $258 million by the end of March. It attributed this to working capital requirements.
“The continuing challenges in the diamond market and the weaker sales do not bode well given the ongoing negotiations to refinance Petra’s debt obligations,” Raj Ray, an analyst at BMO Capital Markets, wrote on Monday.
Petra has been restructuring to cut costs, including the sale of its stake in Koffiefontein in October and the recent $16 million sale of the Williamson mine in Tanzania.
Petra shares fell almost 3.5% on the news to 19.5 pence each, putting its market cap at about £38 million ($51 million).
A limited relief package has been announced for diamond workers and small manufacturing units in Surat.
The Gujarat state government is responding to widespread job losses and economic hardship among the estimated one million diamond workers in Surat as the global slowdown persists.
The relief package, as detailed by chief minister Bhupendra Patel, will cover school fees for children of jobless diamond artisans in full, subject to certain conditions.
Small diamond manufacturing businesses will be eligible for low-interest loans and a one-year year exemption from the duty charged on their electricity bills.
The move has been given a cautious welcome by the Diamond Worker Union Gujurat, but there are ongoing calls for more comprehensive support, particularly for unregistered workers and families affected by the crisis, as well as for families of diamond workers who have taken their own lives.
The Diamond Certification Laboratory of Australia (DCLA) reaffirms its commitment to providing precise and comprehensive grading for all diamonds, including laboratory-grown stones. This approach ensures consistency, transparency, and informed decision-making across the industry.
While the GIA has announced it will introduce a simplified classification system for lab-grown diamonds — using the categories “Premium” and “Standard” — the DCLA will maintain its tradition of detailed grading across the full range of quality characteristics. This includes reporting actual colour, clarity, cut, and carat weight for every diamond submitted, regardless of its origin.
The GIA’s new system, expected later this year, will group lab-grown diamonds based on overall appearance and finish, with certificates including carat and cut details but without specific colour and clarity grades.
DCLA recognises that both natural and laboratory-grown diamonds hold unique value and significance. By continuing to offer full grading reports, the DCLA supports both the trade and consumers in understanding and appreciating the distinct qualities of each stone.
At DCLA, we believe that consumers and the trade deserve full and detailed grading information, regardless of the diamond’s origin. Misrepresentation and confusion are more likely to arise when simplified or vague grading systems are used — especially as laboratory-grown diamonds become more prevalent in the market.
As Australia’s official CIBJO laboratory, DCLA remains dedicated to upholding the highest international standards in diamond certification and grading.
Sotheby’s New York is set to host an extraordinary High Jewellery auction on 13 June, featuring 110 remarkable lots — many of them centred around colourless and fancy coloured diamonds. This exclusive sale not only showcases some of the most important stones on the market today but also brings to light jewellery with historic provenance, including pieces from the Vanderbilt and Wade families, and a private collection chronicling a decades-long romance.
The Crown Jewel: 35.01ct Graff Diamond Ring Leading the sale is a breathtaking 35.01-carat emerald-cut diamond ring from luxury jeweller Graff. This D-colour, VVS2 clarity diamond is described as “highly important,” and is expected to fetch between USD $2 million and $3 million (approximately AUD $3 million to $4.5 million). It’s one of 13 spectacular jewels from a private collection titled Joie de Vivre: Journey in Jewels — a tribute to a husband’s enduring love, with each piece gifted to his wife throughout a 60-year marriage.
Another standout from the same collection is a pair of emerald and diamond earclips by Graff, boasting four sugarloaf cabochon emeralds weighing a total of approximately 84 carats. These exceptional earrings carry a presale estimate of USD $800,000 – $1.5 million.
Additional highlights from this private collection include:
An aquamarine and diamond bracelet: USD $40,000 – $60,000
A jade and diamond pendant-brooch, circa 1910s: USD $25,000 – $35,000
Fancy Colours Steal the Spotlight The number two lot of the sale is a striking 5.02-carat fancy pink diamond ring with VS2 clarity, estimated at USD $1.5 million – $2.5 million. Following closely is a 2.02-carat fancy vivid blue diamond ring, cut in a modified rectangular mixed style, with an estimate of USD $1.4 million – $1.8 million.
Also drawing significant attention is a pair of flawless D-colour pear-shaped diamonds weighing 10.32 and 10.11 carats respectively. Both diamonds are rated “excellent” in polish and symmetry, with a combined estimate of USD $1.1 million – $1.5 million.
American Legacy: Vanderbilt and Wade Family Heirlooms Among the historic highlights is a ruby and diamond sautoir by Marcus & Co., dating back to circa 1915. The centrepiece is a 9.60-carat unheated Burmese ruby, surrounded by old European-cut diamonds and accented with calibre-cut rubies. This important jewel is estimated at USD $1 million – $2 million and once belonged to Emily Vanderbilt Wade, the great-granddaughter of Cornelius Vanderbilt and daughter of Rhode Island Governor William Henry Vanderbilt III.
Three other Vanderbilt Wade jewels will also go under the hammer:
Cartier Art Deco diamond bracelet: Estimated at USD $60,000 – $80,000
Rene Lalique Art Nouveau pendant: Crafted from gold, enamel, emerald and pearl, circa 1900, with an estimate of USD $20,000 – $30,000
Multistone tassel sautoir: Featuring rubies, emeralds, pearls, diamonds and enamel, and possibly designed by Paulding Farnham of Tiffany & Co., with an estimate of USD $40,000 – $60,000
A Rare Opportunity for Collectors and Connoisseurs This Sotheby’s auction is not only a chance to acquire some of the world’s most exquisite diamonds and gemstones but also to own a piece of history. With provenance linking to America’s most prominent families and jewellery houses such as Graff, Cartier, and Tiffany & Co., the pieces represent both artistic excellence and emotional legacy.
For collectors, investors, and jewellery lovers alike, 13 June will mark a significant date on the global jewellery calendar.
In a landmark decision that will reverberate through the global diamond industry, the Gemological Institute of America (GIA) the world’s foremost authority in gemology—has announced it will no longer use its internationally recognized 4Cs grading system for laboratory-grown diamonds. Instead, beginning later this year, lab-grown diamonds submitted to GIA will receive simplified descriptors—categorized broadly as either “premium” or “standard”—or no grade at all if the quality is subpar.
While GIA’s move to redefine lab grown diamond grading might sound like a simple nomenclature change, it’s much more than that. This move marks a definitive moment in the ongoing separation of natural diamonds from lab-grown diamonds. It confirms what many in the industry have long known: lab-grown diamonds are not the same as natural diamonds and should not be treated as such.
Why the 4Cs Is Essential for Natural Diamonds
GIA created the 4Cs—cut, color, clarity, and carat weight—as a rigorous system to help consumers understand the unique and complex qualities of natural diamonds. No two natural diamonds are exactly alike. They are rare geological miracles forged deep within the Earth over billions of years, each carrying a singular fingerprint from Mother Nature. A grading report for a natural diamond is essential because these stones exist along an immense spectrum of characteristics.
Meet the Expert
Grant Mobley is the Jewelry & Watch Editor of Only Natural Diamonds.
He is a GIA Diamonds Graduate.
He has over 17 years of jewelry industry experience, starting with growing up in his family’s retail jewelry stores.
An uncut lab grown diamond
Why GIA Is Changing the Way Lab Grown Diamonds Are Graded
Lab-grown diamonds, on the other hand, are man-made and mass-produced using high-pressure high-temperature (HPHT) or Chemical Vapor Deposition (CVD) processes. According to Tom Moses, GIA executive vice president and chief laboratory and research officer, “More than 95% of laboratory-grown diamonds entering the market fall into a very narrow range of color and clarity. Because of that, it is no longer relevant for GIA to describe man-made diamonds using the nomenclature created for the continuum of color and clarity of natural diamonds.”Why Lab Grown Diamond Grading Needs a Different System
By replacing detailed grading reports with broader descriptors, such as “premium” and “standard,” GIA is drawing a clear line in the sand. They are telling consumers that these are not the same products and they should not be evaluated in the same way. And coming from GIA—the trusted nonprofit organization that established global diamond grading standards in 1953—this statement couldn’t be more authoritative.
Natural Diamonds: Rarity, Value, and Geological Identity
To understand why this change to lab grown diamond grading matters, it’s essential to examine what drives the value of natural diamonds: rarity and identity. Each natural diamond is finite, with unique growth patterns, internal inclusions, and color subtleties shaped by millions or even billions of years underground. These one-of-a-kind gems are the original luxury product—not just beautiful but rare and no longer forming in nature. Lab-grown diamonds, conversely, can be created in virtually unlimited quantities and replicated in appearance with astonishing ease. There is no rarity. There is no geological story. There is no true investment potential.
Ring Courtesy of The Clear Cut
Why Clarity in Lab Grown Diamond Grading Matters for Consumers
This distinction has become increasingly blurred by confusing marketing language and unclear labeling practices. Some in the lab-grown diamond space have leaned on the unsubstantiated language of “sustainability” and “equality” in comparison to natural diamonds, despite offering a fundamentally different product. But consumers deserve transparency. They deserve to understand what they’re buying, what it’s worth, and what makes one stone different from another. That’s precisely why this change from GIA is so important.
It’s also a return to the Institute’s founding principles. GIA exists to protect the public trust in gems and jewelry. With this shift, the Institute is ensuring that consumers can make informed choices without being misled by false equivalencies. By stepping away from the 4Cs for lab-grown diamonds, GIA is reaffirming its commitment to scientific integrity and public transparency.
GIA Diamond Grading Report
Let me be clear: This is not about pitting one product against another. Lab-grown diamonds have their place in the market. But we must stop pretending they are interchangeable with natural diamonds. They are not heirlooms, they are not investments, and they are not rare.
GIA’s decision demonstrates that natural diamonds continue to be the benchmark of authenticity, value, and irreplaceability. They are not merely carbon crystals—they are ancient, unrepeatable creations of nature, each with a backstory written in geologic time.
As this policy rolls out in late 2025, expect other gem labs to follow suit. The line separating lab-created simulacra and natural geological masterpieces is being redrawn with bold ink—and GIA is holding the pen.
Jewelers based in Dubai have set a world record with a diamond-stud necklace that’s 108 meters long.
Amaar Jewels was officially certified by Guinness World Records after crafting the piece from 650 grams of rose gold and more 600 hand-set lab grown diamonds.
It took 60 days to make what Amaar called “one continuous masterpiece”.
The necklace was displayed for the first time at the the 55th Watch and Jewellery Middle East Show (WJMES), which opened on 28 May at Expo Centre Sharjah, UAE, with more than 500 exhibitors 1,800 designers and manufacturers and over 80,000 visitors expected.
The difference in diamond grading between laboratories like GIA (Gemological Institute of America) and DCLA (Diamond Certification Laboratory of Australia) can occur due to the subjective nature of diamond grading and variations in grading standards, tools, and methodology.
Here’s a detailed explanation of why this happens:
Example of a diamond graded GIA E VS2 vs DCLA F SI1:
1. Grading is Subjective to Some Extent
Even though labs follow international grading systems like those defined by CIBJO or GIA, colour and clarity grading involves human judgment under magnification and controlled lighting conditions. Two experienced graders may interpret borderline characteristics differently.
Colour: E and F are adjacent grades, and the difference is extremely subtle—often imperceptible to the untrained eye.
Clarity: The distinction between VS2 (Very Slightly Included 2) and SI1 (Slightly Included 1) can also hinge on size, position, nature, and number of inclusions, which may be judged differently by separate labs.
2. Different Lab Philosophies
GIA is widely considered the global benchmark for consistency and tends to be more conservative in some grading aspects, especially in colour.
DCLA, while highly respected and CIBJO-accredited (and Australia’s official diamond authority), might interpret certain characteristics differently based on their internal grading protocols.
3. Grading Conditions and Equipment
Minor differences in:
Lighting
Magnification tools
Grading environments can affect the appearance of a diamond, especially in borderline cases.
4. Grading Date and Re-evaluation
Grading can differ if:
The diamond was graded at different times.
The diamond was repolished or slightly recut between submissions.
The grader has different levels of training or experience (even within the same lab over time).
5. Lab-to-Lab Variance Is a Known Industry Factor
Even among top labs (GIA, IGI, HRD, AGS, DCLA), 1-grade differences in colour or clarity are common and not considered errors. This is why many dealers and appraisers say a difference of one colour or clarity grade is within acceptable tolerance.
In Your Example:
GIA E VS2 vs DCLA F SI1:
The colour difference (E vs F): within acceptable tolerance; both are considered colourless.
The clarity difference (VS2 vs SI1): SI1 is a full grade lower, but this could be due to:
An inclusion judged more impactful by DCLA
A stricter application of clarity grading by DCLA
GIA possibly being more lenient on that particular clarity characteristic
Differences like GIA E VS2 and DCLA F SI1 can result from:
Subjective human interpretation
Slightly different grading standards
Borderline characteristics
Environmental and technical grading factors
For buyers or sellers, it’s important to:
Always compare certificates from top-tier labs.
Understand that 1-grade discrepancies are common.
Consider getting a professional review if there’s a significant value implication.
Graff has opened its biggest store in North America, at the Fontainebleau Las Vegas luxury resort and casino.
The 3,300sq ft showroom is second only to the flagship Graff in Paris, at 3,700sq ft.
Graff, founded in 1960 by British jeweler Laurence Graff, is recognized as one of the world’s most prestigious luxury jewelers.
CEO Francois Graff (Laurence’s son) said: “The opening of our new salon at Fontainebleau Las Vegas represents a pivotal moment for Graff in North America, a testament to our continued success and commitment to expansion across the region.”
The Las Vegas store is the brand’s 10th location in North America. It has more than 50 worldwide.
The new showroom features a serpentine counter with angular displays inspired by diamond facets, a bespoke bridal area with engagement rings, wedding bands, and bridal jewelry crafted from celadon wood and chiseled glass.
To celebrate the opening, Graff has curated a special selection of high jewelry featuring rare diamonds, emeralds, rubies, and sapphires.
